CVE-2026-83646 Active Directory Federation Services (AD FS) Spoofing Vulnerability
An authorized attacker can exploit an open redirect in AD FS to perform spoofing attacks over the network.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-83646?
CVE-2026-83646 is a medium-severity vulnerability in Microsoft Windows 10 1607, published on 13 Oct 2026. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.
Official description
Url redirection to untrusted site ('open redirect') in Active Directory Federation Services (AD FS) allows an authorized attacker to perform spoofing over a network.
Weakness: CWE-601
Which versions are affected by CVE-2026-83646?
It affects 6 products.
Products include Microsoft Windows 10 1607, Microsoft Windows 10 1809, Microsoft Windows Server 2016, Microsoft Windows Server 2019, Microsoft Windows Server 2022, Microsoft Windows Server 2025.
How do I fix CVE-2026-83646?
No fix has been published for CVE-2026-83646 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-83646 being exploited?
There is no known exploitation of CVE-2026-83646 in the wild and no public exploit code.
Other vulnerabilities in Microsoft Windows 10 1607
- CVE-2026-33824 Microsoft Internet Key Exchange (IKE) Service Extensions Double Free
- CVE-2026-21510 Microsoft Windows Shell Protection Mechanism Failure
- CVE-2026-21513 Microsoft MSHTML Framework Protection Mechanism Failure
- CVE-2023-32049 Microsoft Windows Defender SmartScreen Security Feature Bypass
- CVE-2023-29360 Microsoft Streaming Service Untrusted Pointer Dereference
Sources
Also known as GHSA-3chv-67xr-9w88.